Deposits - Summary (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Banking and Thrift [Abstract]
Interest-bearing Deposit Liabilities	$ 9,503,559	$ 9,239,554
Noninterest-bearing Deposit Liabilities	42,455	55,036
Deposits at Sallie Mae Bank	9,546,014	9,294,590
Deposit with subsidiary	(655,805)	(293,040)
Deposits	$ 8,890,209	$ 9,001,550

Deposits at Sallie Mae Bank

No definition available.

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- Definition

Deposit with subsidiary

+ References

No definition available.

+ Details

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- Details

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- Definition

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.12)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 9

+ Details

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- Definition

The aggregate of all domestic and foreign interest-bearing deposit liabilities.

+ References

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- Definition

The aggregate amount of all domestic and foreign noninterest-bearing deposits liabilities held by the entity.

+ References

+ Details

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